1. Field of the Invention
This invention relates to long lasting detergent bars. More particularly, the invention relates to a composition of heat stable, water-soluble polymers distributed through a surfactant bar. Polymerization of water-soluble polyamides or polyesters in the presence of a surface active agent or melt blending produces a persistent, though water-soluble composition which can be molded or shaped as detergent bars, toys and other useful articles.
2. Description of the Useful Arts
Detergent or soap bars have long been used for washing the human body, laundering clothing or cleaning kitchenware. The solid bar is a convenient means of dispensing the surface active agent at the point of use. These solid bars have comprised additional components, such as abrasives to enhance the cleaning qualities of the bar.
U.S. Pat. No. 4,190,550 describes a soap-filled pad. Needled and crimped synthetic organic fibers are imbedded in a solid soap core. The synthetic fibers may comprise nylon fibers 150 to 200 microns in diameter and 3 cm. in length and may be oriented to provide resilience and strength. Thinner, supple acetate rayon fibers of 20 to 50 micron diameters are more suited to bathing.
U.S. Pat. No. 3,949,137 describes a unitary body sponge having a selected porosity, impregnated with a gel material comprising synthetic detergents or soap. The sponge contains 70 to 200 pores per square inch.
Surface active agents have properties which make them useful for applications other than washing. They are known for their use as mold release or solubility agents.
U.S. Pat. No. 4,217,324 describes the use of a surfactant to uniformly disperse a lubricant through molten nylon during molding to produce an antifriction nylon member. The surfactant has no function once the molten nylon member has cooled and solidified.
U.S. Pat. No. 4,320,213 describes the use of a surfactant as an emulsifier in the polymerization of a polyamide resin with an elastomer. The molded product is a high impact polyamide suitable for automotive parts, gears and the like.
U.S. Pat. No. 3,882,090 describes the use of linear water-soluble polyamides having ether linkages in the polymer chain which are used as textile sizing agents, coatings and adhesives.
U.S. Pat. No. 3,654,167 describes water insoluble polyamides made from fatty acids, diacids, triacids, etc. with aliphatic, cycloaliphatic or aromatic diamines.
U.S. Pat. No. 4,193,887 describes polyurethane sponges containing alkyl aryl sulfonate detergents. The polyol and detergent are mixed and then allowed to react with a polyisocyanate in the presence of water. The polyols are water insoluble and so is the polyurethane. The products are water insoluble flexible urethane foams filled with detergent.
U.S. Pat. Nos. 4,207,198 and 4,554,097 describe an improved elastic bar and elastic detergent product which comprises an organic detergent with gelatin and a lower di- or polyhydric alcohol.
U.S. Pat. No. 4,323,656 describes sponges made by entraping soaps in the sponge using diisocyanates and polyethers or polyester. The sponges are not water-soluble, nor are they polyamides or polyesters.